1. Field of the Invention
The invention in general relates to fluid detectors and in particular to a method and apparatus for placing a fluid detector probe in confined areas, such as the space between the walls of a double-walled tank.
2. Description of the Prior Art
Fluid detector probes that differentiate between polar and non-polar liquids and gases have been used for some time to detect hydrocarbon pollutants. They have become particularly important in detecting the presence of leaks in tanks containing gasoline or oil. See, for example, U.S. Pat. Nos. 4,116,045 issued to Bronson M. Potter, 4,221,125 issued to John N. Oliver and Louis M. Sandler and 4,442,405 issued to Raymond J. Andrejasich and Ralph A. Perry and U.S. patent application Ser. No. 06/579,431 on an invention of Raymond J. Andrejasich.
While these detector probes have become progressively more reliable, they have not been employed in some locations, such as between the walls of a double-walled tank, where it would be highly useful to detect hydrocarbons. This has been a significant problem in the industry because correction of a leak in the inner wall of a double-walled tank is usually relatively inexpensive, as compared to the cleanup that can be required upon leakage through both walls. Thus a method and apparatus by which such detector probes may be accurately placed between the walls of a double-walled tank is highly desirable.